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91.
Structural Chemistry - The N-methyl-D-aspartate (NMDA) is the family of glutamate receptor, which is involved in controlling synaptic plasticity and memory function; but overactivation of this...  相似文献   
92.
Benzophenone azine crystallizes in the monoclinic space groupA2/a (No. 15) witha=16.303(3) Å,b=5.4864(2) Å,c=21.973(5) Å, =85.52(2)°,V=1959.4(8) Å3, andD calc=1.22 g cm–3 forZ=4. The structure was solved by direct methods and refined againstF to a finalR value of 0.047. The unit cell contains four molecules of the title compound; the asymmetric unit consists of half a molecule. Despite the high crystallographic symmetry, the two halves of the molecule arenot related by a center of symmetry; instead, the molecule adopts C2 symmetry; the molecular C2 axis is coincident with the crystallographic twofold axis. The formation of benzophenone azine from the reaction of the iron-containing Lewis acid complex [(5-C5H5)Fe(CO)2(THF)]+ [BF4] and diphenyldiazomethane provides strong evidence for an Fe(II) carbene intermediate.  相似文献   
93.
Decacarbonyl--hydrido--1,8-2-quinoline-triosmium crystallizes in the triclinic space group P with a = 7.8551(6), b = 9.1283(8), c = 16.7915(8) Å, = 74.788(2), = 88.086(2), = 66.392(3)°, V = 1062.22(13)° Å3, T = 150 K, and Z = 2. The molecule consists of an Os3 triangle with the hydride and the heterocyclic ligand bridging the same Os—Os edge. The heterocyclic ligand is coordinated through the C(8) carbon and nitrogen atoms in a new -1,8-2-bonding mode. The Os—Os distances lie in the close range 2.8837(4)–2.9034(4) Å with an average value of 2.892(7) Å.  相似文献   
94.
Three different types of metal-organic polymers have been prepared by a solution diffusion process carried out at room temperature. Crystals of the copper coordination polymers [CuX(4,4′-bipy)] n (X = Cl, Br, I) have been obtained by the reaction of 4,4′-bipyridine ligands with Cu2X2 fragments to yield a three-dimensional network consisting of four interlocking planar lattices. Single crystals of [Cu2(1,2,4,5-BTC)(DMF)2] n (1,2,4,5-BTC = 1,2,4,5-benzene tetracarboxylate) have been grown by slow diffusion from solutions of a mixture of CuBr2, 2,2′-dithiosalicylic acid, and sodium azide plus a mixture of 1,2,4,5-H4BTC and 4-cyanopyridine. The complex [Co(1,3,5-BTC)(4,4′-bipy)] n (1,3,5-BTC = 1,3,5-benzene tricarboxylate) has a 3D open framework structure involving terminal cobalt atoms plus bridging 1,3,5-BTC and 4,4′-bipyridine ligands.  相似文献   
95.
Although mesoporous metals have been synthesized by electrochemical methods, the possible compositions have been limited to noble metals (e.g., palladium, platinum, gold) and their alloys. Herein we describe the first fabrication of continuously mesoporous Cu films using polymeric micelles as soft templates to control the growth of Cu under sophisticated electrochemical conditions. Uniformly sized mesopores are evenly distributed over the entire film, and the pore walls are composed of highly crystalized Cu.  相似文献   
96.
To explore the role of competing forward and reversed chain reactions in the growth of a one-dimensional (1D) molecular line on the Si(100)-(2 x 1)-H surface, controlled experiments were performed with various alkene molecules by scanning tunneling microscopy (STM) at various temperatures. It was observed that the end dangling bond (DB) of a styrene line, fabricated by a chain reaction on the Si(100)-(2 x 1)-H surface at 300 K, initiated a reverse chain reaction at 400 K, leading to the complete disappearance of the styrene line with zero-order desorption kinetics (rate constant k = 1.17 x 10-2 s-1 at 400 K). In the case of 2,4-dimethylstyrene, the reversed chain reaction was observed even at 300 K. These results suggest that the appearance of a molecular line in an STM image is determined by the rates of competing forward and reversed chain reactions at a given temperature. As predicted, 1D lines formed by the DB-initiated chain reaction of 1-hexene and 1-heptene on Si(100)-(2 x 1)-H were observed at 180 K because of the reduced desorption rate, despite the fact that those molecules showed no line growth at 300 K. These results indicate that the scope of forming 1D molecular lines on the Si(100)-(2 x 1)-H surface with various alkenes is much wider than anticipated in previous studies.  相似文献   
97.
The crystal structures of two metallo oxides, perrhenate and dichromate, are reported with a diprotonated tetraamido/diamino-based macrocycle, L, in which the floppy ligand assumes a folded conformation. When the four amides are deprotonated, this same ligand binds transition-metal ions in its tetraanionic form, H-4L. For the divalent metal ions Cu2+ and Ni2+, H-4L again folds and dinuclear complexes are formed. With trivalent metal ions Co3+ and Fe3+, the ligand wraps about the metal ions, resulting in mononuclear complexes.  相似文献   
98.
Biofortification of pulse crops with Zn and Fe is a viable approach to combat their widespread deficiencies in humans. Lentil (Lens culinaris Medik.) is a widely consumed edible crop possessing a high level of Zn and Fe micronutrients. Thus, the present study was conducted to examine the influence of foliar application of Zn and Fe on productivity, concentration, uptake and the economics of lentil cultivation (LL 931). For this, different treatment combinations of ZnSO4·7H2O (0.5%) and FeSO4·7H2O (0.5%), along with the recommended dose of fertilizer (RDF), were applied to the lentil. The results of study reported that the combined foliar application of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at pre-flowering (S1) and pod formation (S2) stages was most effective in enhancing grain and straw yield, Zn and Fe concentration, and uptake. However, the outcome of this treatment was statistically on par with the results obtained under the treatment ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage. A single spray of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage enhanced the grain and straw yield up to 39.6% and 51.8%, respectively. Similarly, Zn and Fe concentrations showed enhancement in grain (10.9% and 20.4%, respectively) and straw (27.5% and 27.6% respectively) of the lentil. The increase in Zn and Fe uptake by grain was 54.8% and 68.0%, respectively, whereas uptake by straw was 93.6% and 93.7%, respectively. Also the benefit:cost was the highest (1.96) with application of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage. Conclusively, the combined use of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage can contribute significantly towards yield, Zn and Fe concentration, as well as uptake and the economic returns of lentil to remediate the Zn and Fe deficiency.  相似文献   
99.
100.
Physics of Atomic Nuclei - The even—even rare-earth nuclei in U(5)—SU(3) region at neutron number (N) = 90, have been systematically studied using the Bohr—Mottelson Model (BM),...  相似文献   
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